William F. Masterson III - 12 Dec 2025 Form 4 Insider Report for CABOT CORP (CBT)

Role: Senior Vice President
Signature: By: Jennifer Lombardi, pursuant to a power of attorney from William F. Masterson, III
Issuer symbol: CBT
Transactions as of: 12 Dec 2025
Transactions value $: $130
Form type: 4
Filing time: 16 Dec 2025, 17:00:08 UTC
Previous filing: 05 Dec 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Masterson William F III	Senior Vice President	C/O CABOT CORPORATION, TWO SEAPORT LANE, SUITE 1400, BOSTON	By: Jennifer Lombardi, pursuant to a power of attorney from William F. Masterson, III	16 Dec 2025	0002098902

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	CBT	Phantom Stock Units	Award	$130	+1.91	+0.66%	$68.34	292	12 Dec 2025	Common Stock	1.91		Direct	F1, F2

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	1 for 1
F2	Represents dividends paid on phantom stock units acquired under the Corporation's Supplemental 401(k) Plan and are to be settled upon the reporting person's retirement or other termination of employment.